Allocate the struct rpcrdma_regbuf separately from the I/O buffer
to better guarantee the alignment of the I/O buffer and eliminate
the wasted space between the rpcrdma_regbuf metadata and the buffer
itself.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
For code legibility, clean up the function names to be consistent
with the pattern: "rpcrdma" _ object-type _ action
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Eventually, I'd like to invoke rpcrdma_create_req() during the
call_reserve step. Memory allocation there probably needs to use
GFP_NOIO. Therefore a set of GFP flags needs to be passed in.
As an additional clean up, just return a pointer or NULL, because
the only error return code here is -ENOMEM.
Lastly, clean up the function names to be consistent with the
pattern: "rpcrdma" _ object-type _ action
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
After a DMA map failure in frwr_map, mark the MR so that recycling
won't attempt to DMA unmap it.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Fixes: e2f34e2671 ("xprtrdma: Yet another double DMA-unmap")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Page allocation requests made when the SPARSE_PAGES flag is set are
allowed to fail, and are not critical. No need to spend a rare
resource.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add the 'softerr' rpc client flag that sets the RPC_TASK_TIMEOUT
flag on all new rpc tasks that are attached to that rpc client.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In particular, the timeout messages can be very noisy, so we ought to
ratelimit them in order to avoid spamming the syslog.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
When calculating the major timeout for a new task, when we know that the
connection has been broken, use the task->tk_start to ensure that we also
take into account the time spent waiting for a slot or session slot. This
ensures that we fail over soft requests relatively quickly once the
connection has actually been broken, and the first requests have
started to fail.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
If a soft NFSv4 request is sent, then we don't need it to time out unless
the connection breaks. The reason is that as long as the connection is
unbroken, the protocol states that the server is not allowed to drop the
request. IOW: as long as the connection remains unbroken, the client may
assume that all transmitted RPC requests are being processed by the server,
and that retransmissions and timeouts of those requests are unwarranted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add variables to track RPC level errors so that we can distinguish
between issue that arose in the RPC transport layer as opposed to
those arising from the reply message.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Ensure that when in the transport layer, we don't sleep past
a major timeout.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Don't wake idle CPUs only for the purpose of servicing an RPC
queue timeout.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Simplify the setting of queue timeouts by using the timer_reduce()
function.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add a helper to ensure that debugfs and friends print out the
correct current task timeout value.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up the RPC task sleep interfaces by replacing the task->tk_timeout
'hidden parameter' to rpc_sleep_on() with a new function that takes an
absolute timeout.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
None of the callers set the 'action' argument, so let's just remove it.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
rpc_sleep_on() does not need to set the task->tk_callback under the
queue lock, so move that out.
Also refactor the check for whether the task is active.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Convert the transport callback to actually put the request to sleep
instead of just setting a timeout. This is in preparation for
rpc_sleep_on_timeout().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The RPC_TASK_KILLED flag should really not be set from another context
because it can clobber data in the struct task when task->tk_flags is
changed non-atomically.
Let's therefore swap out RPC_TASK_KILLED with an atomic flag, and add
a function to set that flag and safely wake up the task.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.
With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP. These would all need to be fixed if any shash algorithm
actually started sleeping. For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API. However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.
Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk. It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.
Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
rsi_parse() is part of a downcall, so we must assume that the uids
and gids are encoded using the current user namespace.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
gid_parse() is part of a downcall, so uids and gids should be assumed
encoded using the current user namespace.
svcauth_unix_accept() is, on the other hand, decoding uids and gids from
the wire, so we assume those are encoded to match the user namespace of
the server process.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Temporary sockets should inherit the credential (and hence the user
namespace) from the parent listener transport.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In order to be able to interpret uids and gids correctly in knfsd, we
should cache the user namespace of the process that created the RPC
server's listener. To do so, we refcount the credential of that process.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a callback to allow customisation of the rpcbind registration.
When clients have the ability to turn on and off version support,
we want to allow them to also prevent registration of those
versions with the rpc portmapper.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Simplify the generic server dispatcher.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Add a callback to help initialise server requests before they are
processed. This will allow us to clean up the NFS server version
support, and to make it container safe.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
RPC server procedures are normally expected to return a __be32 encoded
status value of type 'enum rpc_accept_stat', however at least one function
wants to return an authentication status of type 'enum rpc_auth_stat'
in the case where authentication fails.
This patch adds functionality to allow this.
Fixes: a4e187d83d ("NFS: Don't drop CB requests with invalid principals")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
If no handler (such as rpc.mountd) has opened
a cache 'channel', the sunrpc cache responds to
all lookup requests with -ENOENT. This is particularly
important for the auth.unix.gid cache which is
optional.
If the channel was open briefly and an upcall was written to it,
this upcall remains pending even when the handler closes the
channel. When an upcall is pending, the code currently
doesn't check if there are still listeners, it only performs
that check before sending an upcall.
As the cache treads a recently closes channel (closed less than
30 seconds ago) as "potentially still open", there is a
reasonable sized window when a request can become pending
in a closed channel, and thereby block lookups indefinitely.
This can easily be demonstrated by running
cat /proc/net/rpc/auth.unix.gid/channel
and then trying to mount an NFS filesystem from this host. It
will block indefinitely (unless mountd is run with --manage-gids,
or krb5 is used).
When cache_check() finds that an upcall is pending, it should
perform the "cache_listeners_exist()" exist test. If no
listeners do exist, the request should be negated.
With this change in place, there can still be a 30second wait on
mount, until the cache gives up waiting for a handler to come
back, but this is much better than an indefinite wait.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
lock-notification callbacks, NFSv3 readdir encoding, and the
cache/upcall code.
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Merge tag 'nfsd-5.1-1' of git://linux-nfs.org/~bfields/linux
Pull nfsd bugfixes from Bruce Fields:
"Fix miscellaneous nfsd bugs, in NFSv4.1 callbacks, NFSv4.1
lock-notification callbacks, NFSv3 readdir encoding, and the
cache/upcall code"
* tag 'nfsd-5.1-1' of git://linux-nfs.org/~bfields/linux:
nfsd: wake blocked file lock waiters before sending callback
nfsd: wake waiters blocked on file_lock before deleting it
nfsd: Don't release the callback slot unless it was actually held
nfsd/nfsd3_proc_readdir: fix buffer count and page pointers
sunrpc: don't mark uninitialised items as VALID.
If a request transmission fails due to write space or slot unavailability
errors, but the queued task then gets transmitted before it has time to
process the error in call_transmit_status() or call_bc_transmit_status(),
we need to suppress the transmission error code to prevent it from leaking
out of the RPC layer.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
This reverts commit 009a82f643.
The ability to optimise here relies on compiler being able to optimise
away tail calls to avoid stack overflows. Unfortunately, we are seeing
reports of problems, so let's just revert.
Reported-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We want to drain only the RQ first. Otherwise the transport can
deadlock on ->close if there are outstanding Send completions.
Fixes: 6d2d0ee27c ("xprtrdma: Replace rpcrdma_receive_wq ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # v5.0+
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
A recent commit added a call to cache_fresh_locked()
when an expired item was found.
The call sets the CACHE_VALID flag, so it is important
that the item actually is valid.
There are two ways it could be valid:
1/ If ->update has been called to fill in relevant content
2/ if CACHE_NEGATIVE is set, to say that content doesn't exist.
An expired item that is waiting for an update will be neither.
Setting CACHE_VALID will mean that a subsequent call to cache_put()
will be likely to dereference uninitialised pointers.
So we must make sure the item is valid, and we already have code to do
that in try_to_negate_entry(). This takes the hash lock and so cannot
be used directly, so take out the two lines that we need and use them.
Now cache_fresh_locked() is certain to be called only on
a valid item.
Cc: stable@kernel.org # 2.6.35
Fixes: 4ecd55ea07 ("sunrpc: fix cache_head leak due to queued request")
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Avoid following compiler warning on uninitialized variable
net/sunrpc/xprtsock.c: In function ‘xs_read_stream_request.constprop’:
net/sunrpc/xprtsock.c:525:10: warning: ‘read’ may be used uninitialized in this function [-Wmaybe-uninitialized]
return read;
^~~~
net/sunrpc/xprtsock.c:529:23: warning: ‘ret’ may be used uninitialized in this function [-Wmaybe-uninitialized]
return ret < 0 ? ret : read;
~~~~~~~~~~~~~~^~~~~~
Signed-off-by: Alakesh Haloi <alakesh.haloi@gmail.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the transport is still connected, then we do want to allow
RPC_SOFTCONN tasks to retry. They should time out if and only if
the connection is broken.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Highlights include:
Bugfixes:
- Fix an Oops in SUNRPC back channel tracepoints
- Fix a SUNRPC client regression when handling oversized replies
- Fix the minimal size for SUNRPC reply buffer allocation
- rpc_decode_header() must always return a non-zero value on error
- Fix a typo in pnfs_update_layout()
Cleanups:
- Remove redundant check for the reply length in call_decode()
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Merge tag 'nfs-for-5.1-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client bugfixes from Trond Myklebust:
"Highlights include:
Bugfixes:
- Fix an Oops in SUNRPC back channel tracepoints
- Fix a SUNRPC client regression when handling oversized replies
- Fix the minimal size for SUNRPC reply buffer allocation
- rpc_decode_header() must always return a non-zero value on error
- Fix a typo in pnfs_update_layout()
Cleanup:
- Remove redundant check for the reply length in call_decode()"
* tag 'nfs-for-5.1-2' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Remove redundant check for the reply length in call_decode()
SUNRPC: Handle the SYSTEM_ERR rpc error
SUNRPC: rpc_decode_header() must always return a non-zero value on error
SUNRPC: Use the ENOTCONN error on socket disconnect
SUNRPC: Fix the minimal size for reply buffer allocation
SUNRPC: Fix a client regression when handling oversized replies
pNFS: Fix a typo in pnfs_update_layout
fix null pointer deref in tracepoints in back channel
Now that we're using the xdr_stream functions to decode the header,
the test for the minimum reply length is redundant.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Handle the SYSTEM_ERR rpc error by retrying the RPC call as if it
were a garbage argument.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Ensure that when the "garbage args" case falls through, we do set
an error of EIO.
Fixes: a0584ee9ae ("SUNRPC: Use struct xdr_stream when decoding...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
When the socket is closed, we currently send an EAGAIN error to all
pending requests in order to ask them to retransmit. Use ENOTCONN
instead, to ensure that they try to reconnect before attempting to
transmit.
This also helps SOFTCONN tasks to behave correctly in this
situation.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
We must at minimum allocate enough memory to be able to see any auth
errors in the reply from the server.
Fixes: 2c94b8eca1 ("SUNRPC: Use au_rslack when computing reply...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the server sends a reply that is larger than the pre-allocated
buffer, then the current code may fail to register how much of
the stream that it has finished reading. This again can lead to
hangs.
Fixes: e92053a52e ("SUNRPC: Handle zero length fragments correctly")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
that could artificially limit NFSv4.1 performance by limiting the number
of oustanding rpcs from a single client. Neil Brown also gets a special
mention for fixing a 14.5-year-old memory-corruption bug in the encoding
of NFSv3 readdir responses.
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Merge tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux
Pull NFS server updates from Bruce Fields:
"Miscellaneous NFS server fixes.
Probably the most visible bug is one that could artificially limit
NFSv4.1 performance by limiting the number of oustanding rpcs from a
single client.
Neil Brown also gets a special mention for fixing a 14.5-year-old
memory-corruption bug in the encoding of NFSv3 readdir responses"
* tag 'nfsd-5.1' of git://linux-nfs.org/~bfields/linux:
nfsd: allow nfsv3 readdir request to be larger.
nfsd: fix wrong check in write_v4_end_grace()
nfsd: fix memory corruption caused by readdir
nfsd: fix performance-limiting session calculation
svcrpc: fix UDP on servers with lots of threads
svcrdma: Remove syslog warnings in work completion handlers
svcrdma: Squelch compiler warning when SUNRPC_DEBUG is disabled
svcrdma: Use struct_size() in kmalloc()
svcrpc: fix unlikely races preventing queueing of sockets
svcrpc: svc_xprt_has_something_to_do seems a little long
SUNRPC: Don't allow compiler optimisation of svc_xprt_release_slot()
nfsd: fix an IS_ERR() vs NULL check
Before trying to bind a port, ensure we grab the send lock to
ensure that we don't change the port while another task is busy
transmitting requests.
The connect code already takes the send lock in xprt_connect(),
but it is harmless to take it before that.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
In cases where we know the task is not sleeping, try to optimise
away the indirect call to task->tk_action() by replacing it with
a direct call.
Only change tail calls, to allow gcc to perform tail call
elimination.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Before initiating transport actions that require putting the task to sleep,
such as rebinding or reconnecting, we should check whether or not the task
was already transmitted.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
The RPC task wakeup calls all check for RPC_IS_QUEUED() before taking any
locks. In addition, rpc_exit() already calls rpc_wake_up_queued_task().
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Fix a regression where soft and softconn requests are not timing out
as expected.
Fixes: 89f90fe1ad ("SUNRPC: Allow calls to xprt_transmit() to drain...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Now that transmissions happen through a queue, we require the RPC tasks
to handle error conditions that may have been set while they were
sleeping. The back channel does not currently do this, but assumes
that any error condition happens during its own call to xprt_transmit().
The solution is to ensure that the back channel splits out the
error handling just like the forward channel does.
Fixes: 89f90fe1ad ("SUNRPC: Allow calls to xprt_transmit() to drain...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the socket is not connected, then we want to initiate a reconnect
rather that trying to transmit requests. If there is a large number
of requests queued and waiting for the lock in call_transmit(),
then it can take a while for one of the to loop back and retake
the lock in call_connect.
Fixes: 89f90fe1ad ("SUNRPC: Allow calls to xprt_transmit() to drain...")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Now that the reads happen in a process context rather than a softirq,
it is safe to allocate back channel slots using a reclaiming
allocation.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Convert the remaining gfp_flags arguments in sunrpc to standard reclaiming
allocations, now that we set memalloc_nofs_save() as appropriate.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If a layout segment gets invalidated while a pNFS I/O operation
is queued for transmission, then we ideally want to abort
immediately. This is particularly the case when there is a large
number of I/O related RPCs queued in the RPC layer, and the layout
segment gets invalidated due to an ENOSPC error, or an EACCES (because
the client was fenced). We may end up forced to spam the MDS with a
lot of otherwise unnecessary LAYOUTERRORs after that I/O fails.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
udp_poll() checks the struct file for the O_NONBLOCK flag, so we must not
call it with a NULL file pointer.
Fixes: 0ffe86f480 ("SUNRPC: Use poll() to fix up the socket requeue races")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
James Pearson found that an NFS server stopped responding to UDP
requests if started with more than 1017 threads.
sv_max_mesg is about 2^20, so that is probably where the calculation
performed by
svc_sock_setbufsize(svsk->sk_sock,
(serv->sv_nrthreads+3) * serv->sv_max_mesg,
(serv->sv_nrthreads+3) * serv->sv_max_mesg);
starts to overflow an int.
Reported-by: James Pearson <jcpearson@gmail.com>
Tested-by: James Pearson <jcpearson@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that we send the pages using a struct msghdr, instead of
using sendpage(), we no longer need to 'prime the socket' with
an address for unconnected UDP messages.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the client stream receive code receives an ESHUTDOWN error either
because the server closed the connection, or because it sent a
callback which cannot be processed, then we should shut down
the connection.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
If the message read completes, but the socket returned an error
condition, we should ensure to propagate that error.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
A zero length fragment is really a bug, but let's ensure we don't
go nuts when one turns up.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
To ensure that the receive worker has exclusive access to the stream record
info, we must not reset the contents other than when holding the
transport->recv_mutex.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
As reported by Dan Carpenter, this test for acred->cred being set is
inconsistent with the dereference of the pointer a few lines earlier.
An 'auth_cred' *always* has ->cred set - every place that creates one
initializes this field, often as the first thing done.
So remove this test.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Because we clear XPRT_SOCK_DATA_READY before reading, we can end up
with a situation where new data arrives, causing xs_data_ready() to
queue up a second receive worker job for the same socket, which then
immediately gets stuck waiting on the transport receive mutex.
The fix is to only clear XPRT_SOCK_DATA_READY once we're done reading,
and then to use poll() to check if we might need to queue up a new
job in order to deal with any new data.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Set memalloc_nofs_save() on all the rpciod/xprtiod jobs so that we
ensure memory allocations for asynchronous rpc calls don't ever end
up recursing back to the NFS layer for memory reclaim.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
that could prevent clients from reclaiming state after a kernel upgrade.
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Merge tag 'nfsd-5.0-2' of git://linux-nfs.org/~bfields/linux
Pull more nfsd fixes from Bruce Fields:
"Two small fixes, one for crashes using nfs/krb5 with older enctypes,
one that could prevent clients from reclaiming state after a kernel
upgrade"
* tag 'nfsd-5.0-2' of git://linux-nfs.org/~bfields/linux:
sunrpc: fix 4 more call sites that were using stack memory with a scatterlist
Revert "nfsd4: return default lease period"
- Make sure Send CQ is allocated on an existing compvec
- Properly check debugfs dentry before using it
- Don't use page_file_mapping() after removing a page
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Merge tag 'nfs-for-5.0-4' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull more NFS client fixes from Anna Schumaker:
"Three fixes this time.
Nicolas's is for xprtrdma completion vector allocation on single-core
systems. Greg's adds an error check when allocating a debugfs dentry.
And Ben's is an additional fix for nfs_page_async_flush() to prevent
pages from accidentally getting truncated.
Summary:
- Make sure Send CQ is allocated on an existing compvec
- Properly check debugfs dentry before using it
- Don't use page_file_mapping() after removing a page"
* tag 'nfs-for-5.0-4' of git://git.linux-nfs.org/projects/anna/linux-nfs:
NFS: Don't use page_file_mapping after removing the page
rpc: properly check debugfs dentry before using it
xprtrdma: Make sure Send CQ is allocated on an existing compvec
While trying to reproduce a reported kernel panic on arm64, I discovered
that AUTH_GSS basically doesn't work at all with older enctypes on arm64
systems with CONFIG_VMAP_STACK enabled. It turns out there still a few
places using stack memory with scatterlists, causing krb5_encrypt() and
krb5_decrypt() to produce incorrect results (or a BUG if CONFIG_DEBUG_SG
is enabled).
Tested with cthon on v4.0/v4.1/v4.2 with krb5/krb5i/krb5p using
des3-cbc-sha1 and arcfour-hmac-md5.
Signed-off-by: Scott Mayhew <smayhew@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
au_rslack is significantly smaller than (au_cslack << 2). Using
that value results in smaller receive buffers. In some cases this
eliminates an extra segment in Reply chunks (RPC/RDMA).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Currently rpc_inline_rcv_pages() uses au_rslack to estimate the
size of the upper layer reply header. This is fine for auth flavors
where au_verfsize == au_rslack.
However, some auth flavors have more going on. krb5i for example has
two more words after the verifier, and another blob following the
RPC message. The calculation involving au_rslack pushes the upper
layer reply header too far into the rcv_buf.
au_rslack is still valuable: it's the amount of buffer space needed
for the reply, and is used when allocating the reply buffer. We'll
keep that.
But, add a new field that can be used to properly estimate the
location of the upper layer header in each RPC reply, based on the
auth flavor in use.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
au_verfsize will be needed for a non-flavor-specific computation
in a subsequent patch.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Certain NFS results (eg. READLINK) might expect a data payload that
is not an exact multiple of 4 bytes. In this case, XDR encoding
is required to pad that payload so its length on the wire is a
multiple of 4 bytes. The constants that define the maximum size of
each NFS result do not appear to account for this extra word.
In each case where the data payload is to be received into pages:
- 1 word is added to the size of the receive buffer allocated by
call_allocate
- rpc_inline_rcv_pages subtracts 1 word from @hdrsize so that the
extra buffer space falls into the rcv_buf's tail iovec
- If buf->pagelen is word-aligned, an XDR pad is not needed and
is thus removed from the tail
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
prepare_reply_buffer() and its NFSv4 equivalents expose the details
of the RPC header and the auth slack values to upper layer
consumers, creating a layering violation, and duplicating code.
Remedy these issues by adding a new RPC client API that hides those
details from upper layers in a common helper function.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Files under net/sunrpc/auth_gss/ do not yet have SPDX ID tags.
This directory is somewhat complicated because most of these files
have license boilerplate that is not strictly GPL 2.0.
In this patch I add ID tags where there is an obvious match. The
less recognizable licenses are still under research.
For reference, SPDX IDs added in this patch correspond to the
following license text:
GPL-2.0 https://spdx.org/licenses/GPL-2.0.html
GPL-2.0+ https://spdx.org/licenses/GPL-2.0+.html
BSD-3-Clause https://spdx.org/licenses/BSD-3-Clause.html
Cc: Simo Sorce <simo@redhat.com>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
The key action of xdr_buf_trim() is that it shortens buf->len, the
length of the xdr_buf's content. The other actions -- shortening the
head, pages, and tail components -- are actually not necessary. In
particular, changing the size of those components can corrupt the
RPC message contained in the buffer. This is an accident waiting to
happen rather than a current bug, as far as we know.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Bruce Fields <bfields@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Add infrastructure for trace points in the RPC_AUTH_GSS kernel
module, and add a few sample trace points. These report exceptional
or unexpected events, and observe the assignment of GSS sequence
numbers.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Modernize and harden the code path that parses an RPC Reply
message.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
- Recover some instruction count because I'm about to introduce a
few xdr_inline_decode call sites
- Replace dprintk() call sites with trace points
- Reduce the hot path so it fits in fewer cachelines
I've also renamed it rpc_decode_header() to match everything else
in the RPC client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Modernize and harden the code path that constructs each RPC Call
message.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Enable distributions to enforce the rejection of ancient and
insecure Kerberos enctypes in the kernel's RPCSEC_GSS
implementation. These are the single-DES encryption types that
were deprecated in 2012 by RFC 6649.
Enctypes that were deprecated more recently (by RFC 8429) remain
fully supported for now because they are still likely to be widely
used.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Simo Sorce <simo@redhat.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
tsh_size was added to accommodate transports that send a pre-amble
before each RPC message. However, this assumes the pre-amble is
fixed in size, which isn't true for some transports. That makes
tsh_size not very generic.
Also I'd like to make the estimation of RPC send and receive
buffer sizes more precise. tsh_size doesn't currently appear to be
accounted for at all by call_allocate.
Therefore let's just remove the tsh_size concept, and make the only
transports that have a non-zero tsh_size employ a direct approach.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Clean up: Reduce dprintk noise by removing dprintk() call sites
from hot path that do not report exceptions. These are usually
replaceable with function graph tracing.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
We don't want READ payloads that are partially in the head iovec and
in the page buffer because this requires pull-up, which can be
expensive.
The NFS/RPC client tries hard to predict the size of the head iovec
so that the incoming READ data payload lands only in the page
vector, but it doesn't always get it right. To help diagnose such
problems, add a trace point in the logic that decodes READ-like
operations that reports whether pull-up is being done.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
This can help field troubleshooting without needing the overhead of
a full network capture (ie, tcpdump).
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Having access to the controlling rpc_rqst means a trace point in the
XDR code can report:
- the XID
- the task ID and client ID
- the p_name of RPC being processed
Subsequent patches will introduce such trace points.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Post RECV WRs in batches to reduce the hardware doorbell rate per
transport. This helps the RPC-over-RDMA client scale better in
number of transports.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
In very rare cases, an NFS READ operation might predict that the
non-payload part of the RPC Call is large. For instance, an
NFSv4 COMPOUND with a large GETATTR result, in combination with a
large Kerberos credential, could push the non-payload part to be
several kilobytes.
If the non-payload part is larger than the connection's inline
threshold, the client is required to provision a Reply chunk. The
current Linux client does not check for this case. There are two
obvious ways to handle it:
a. Provision a Write chunk for the payload and a Reply chunk for
the non-payload part
b. Provision a Reply chunk for the whole RPC Reply
Some testing at a recent NFS bake-a-thon showed that servers can
mostly handle a. but there are some corner cases that do not work
yet. b. already works (it has to, to handle krb5i/p), but could be
somewhat less efficient. However, I expect this scenario to be very
rare -- no-one has reported a problem yet.
So I'm going to implement b. Sometime later I will provide some
patches to help make b. a little more efficient by more carefully
choosing the Reply chunk's segment sizes to ensure the payload is
optimally aligned.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
debugfs can now report an error code if something went wrong instead of
just NULL. So if the return value is to be used as a "real" dentry, it
needs to be checked if it is an error before dereferencing it.
This is now happening because of ff9fb72bc0 ("debugfs: return error
values, not NULL"), but why debugfs files are not being created properly
is an older issue, probably one that has always been there and should
probably be looked at...
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: linux-nfs@vger.kernel.org
Cc: netdev@vger.kernel.org
Reported-by: David Howells <dhowells@redhat.com>
Tested-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Make sure the device has at least 2 completion vectors
before allocating to compvec#1
Fixes: a4699f5647 (xprtrdma: Put Send CQ in IB_POLL_WORKQUEUE mode)
Signed-off-by: Nicolas Morey-Chaisemartin <nmoreychaisemartin@suse.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
These can result in a lot of log noise, and are able to be triggered
by client misbehavior. Since there are trace points in these
handlers now, there's no need to spam the log.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
CC [M] net/sunrpc/xprtrdma/svc_rdma_transport.o
linux/net/sunrpc/xprtrdma/svc_rdma_transport.c: In function ‘svc_rdma_accept’:
linux/net/sunrpc/xprtrdma/svc_rdma_transport.c:452:19: warning: variable ‘sap’ set but not used [-Wunused-but-set-variable]
struct sockaddr *sap;
^
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:
struct foo {
int stuff;
struct boo entry[];
};
instance = kmalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:
instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
In the rpc server, When something happens that might be reason to wake
up a thread to do something, what we do is
- modify xpt_flags, sk_sock->flags, xpt_reserved, or
xpt_nr_rqsts to indicate the new situation
- call svc_xprt_enqueue() to decide whether to wake up a thread.
svc_xprt_enqueue may require multiple conditions to be true before
queueing up a thread to handle the xprt. In the SMP case, one of the
other CPU's may have set another required condition, and in that case,
although both CPUs run svc_xprt_enqueue(), it's possible that neither
call sees the writes done by the other CPU in time, and neither one
recognizes that all the required conditions have been set. A socket
could therefore be ignored indefinitely.
Add memory barries to ensure that any svc_xprt_enqueue() call will
always see the conditions changed by other CPUs before deciding to
ignore a socket.
I've never seen this race reported. In the unlikely event it happens,
another event will usually come along and the problem will fix itself.
So I don't think this is worth backporting to stable.
Chuck tried this patch and said "I don't see any performance
regressions, but my server has only a single last-level CPU cache."
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>